METHOD FOR DETERMINING FREQUENCY AND AMPLITUDE OF MODULATION OF A PHASE OF A WAVE FRONT GENERATED BY VIBRATIONS OF A CELL MEMBRANE Russian patent published in 2021 - IPC G01N21/41 G01B9/02 G01N33/483 

FIELD: physics.

SUBSTANCE: invention relates to the field of interferometry of phase dynamic objects. Method for determining frequency and amplitude of modulation of a wave front phase generated by vibrations of a cell membrane involves dividing the radiation of a coherent source into two beams, one of which passes through the analyzed object and is displayed on the recorder, and the second passes along the reference channel and also falls on the recorder, where both beams interfere, and change in the interference pattern indicates changes in the phase of the wave front. Reference channel of the interferometer during registration of the interferogram is adjusted so that the value of the phase difference in the selected region is equal to zero. Part of the wave front passed through the analyzed cell is directed by the optical system to the phase modulator. By means of the phase modulator the transmitted radiation with frequency ω₁ and modulation depth m₁, then modulator image is projected by optical system on recorder, wherein to compensate for phase displacement caused by external vibrations, selecting a portion of the wave front not passed through the object, and directed by the same optical system to a phase modulator, which modulates this portion of the wave front by frequency ω₂ and modulation depth m₂. Then image of this part of phase modulator is projected onto recorder, obtained two electric signals are multiplied, and the resulting signal is subjected to spectral analysis, wherein from the signal spectrum, selecting a frequency equal to the difference in the optical radiation modulation frequencies passed through the object, and optical radiation that has not passed through the object, and near this frequency, a symmetrical pair of frequencies with an opposite phase value is searched for, by frequency coordinates of which frequency is determined, and by value - amplitude modulation phase of the wave front in the selected cell region.

EFFECT: technical result consists in providing the possibility of increasing accuracy of measuring frequency and amplitude of membrane cell vibrations.

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